The performance of elements of fixed assets immersed in a context of uncertainty

All elements of fixed asset, even those with the most elementary of technologies imagined by man undergo, as do all living beings, a certain amount of ageing and incidents. Engineers and economists on the one hand and biologists on the other, have in common certain concerns, frequently resorting to related mathematical laws and models. In order to manage an isolated item of fixed assets or one that is immersed in a technological system it is necessary to know how its wear and tear occurs and how and why there appear problems in its operation. What causes more problems are its effects, above all when these are not repetitive or occur on few occasions. No organisation can do without a good operating design for its fixed assets. The knowledge of the characteristics of the items that make this up is important for, at least, establishing “levels” between which the opportune decisions should be taken. K e y w o r d s : Survival , Breakdown, Consumption, Supply, Management, Substitution, Use.